Zone Record Order
Chris Buxton
cbuxton at menandmice.com
Mon Oct 9 18:39:25 UTC 2006
Sorry, didn't mean to cause confusion, but I make it a habit to try
to be strictly accurate.
RRSet reordering involves the order of records in a set when
answering a query. You can configure the BIND 9 name server (at least
9.3.x, anyway) to order a set in round-robin (permuted) order, in a
randomized order, or in the order received or read from file.
However, there's little or no use in specifying anything other than
the default, in my experience. RRSet reordering is a useful thing.
In general, as I said before, other than having the SOA record at the
top of your zone, the order of records in a zone is not considered
relevant. Put them in whatever order is convenient for you, the zone
administrator.
Chris Buxton
Men & Mice
Take control of your network
On Oct 6, 2006, at 1:35 PM, Josh Hyles wrote:
> Hey Kevin, thanks a bunch for the info. I'm still going to have to
> look up RR's as I dont know what that refers to. Please excuse my
> ignorance, as I am not that experienced with BIND/DNS.
>
> I am aware that the transfer is not a "file" transfer, but when he
> said something about RRSet *reordering* I thought maybe there was a
> mechanism in place to order the records for you and thus I thought
> maybe since my master records werent as "pretty" as the slave, then
> maybe something was wrong... but i get it now.
>
> as for the 15 minute TTL, I have that because I am moving mail servers
> and dont have enough servers in place to do fail over. I plan on
> switching them back to 1 day once everything calms down over here.
>
> Josh
>
> On 10/6/06, Kevin Darcy <kcd at daimlerchrysler.com> wrote:
>> An RRset is a group of RRs all having the same owner name, class and
>> type. example.com/IN/MX, for example, defines a unique RRset.
>> example.com/IN, on the other hand, defines only a *name*, and there
>> could be multiple RRsets owned by that name (A, MX, NS, SOA, etc.)
>>
>> I hope you understand that a zone transfer is not a *file*
>> transfer, so
>> the fact that the file format -- including the record order -- may
>> look
>> different between the master and slave is completely irrelevant,
>> as long
>> as the *data* (including the TTL values of the records) is the same.
>>
>> Also, I question why your mail-related records (MX record and
>> associated
>> A record) have a 15-minute TTL at all. Do you have some sort of
>> failover
>> mechanism in place and want to be able to switch those records
>> quickly
>> to point to some other mail server(s)? The proper way to do that
>> is have
>> multiple MX records at different preference values. Then the
>> failover is
>> automatic and you wouldn't have to thrash your DNS and everyone
>> else's
>> DNS with a 15-minute TTL value. Just a suggestion.
>>
>>
>> - Kevin
>>
>> Josh Hyles wrote:
>>> I am not sure what RRSet is, but the slave server does seem to
>>> re-order the record, howerver, the master which i edit, does not
>>> change at all. is that still ok?
>>>
>>> On 10/6/06, Josh Hyles <josh.maillists at gmail.com> wrote:
>>>
>>>> Good point...
>>>>
>>>> One other question.. do I need the "IN" option when doing these?
>>>> I'm
>>>> not sure what it is for, but I've been able to get things
>>>> working for
>>>> the last years with no problem without it.
>>>>
>>>> Josh
>>>>
>>>> On 10/6/06, Chris Buxton <cbuxton at menandmice.com> wrote:
>>>>
>>>>> There's nothing wrong with putting the two records at the end -
>>>>> other
>>>>> than having the SOA record first, the order of records in a
>>>>> zone is
>>>>> usually unimportant. (If you disable RRSet reordering, then
>>>>> order of
>>>>> records in an RRSet becomes important.)
>>>>>
>>>>> Is there a reason not to simply specify a TTL in the two records?
>>>>> Like this:
>>>>>
>>>>> @ 900 MX 5 mail.cvlsoft.net.
>>>>> mail 900 A 12.45.64.7
>>>>>
>>>>> Chris Buxton
>>>>> Men & Mice
>>>>> Take control of your network
>>>>>
>>>>> On Oct 6, 2006, at 11:21 AM, Josh Hyles wrote:
>>>>>
>>>>>
>>>>>> Sent this out as the wrong subject line, sorry.
>>>>>>
>>>>>> On 10/6/06, Josh Hyles <josh.maillists at gmail.com> wrote:
>>>>>>
>>>>>>> Here is my record....
>>>>>>>
>>>>>>> $TTL 86400 ; 1 day
>>>>>>> @ IN SOA ns1.goatinatree.com.
>>>>>>> root.cvlsoft.net. (
>>>>>>> 2006100605 ; serial number
>>>>>>> 3600 ; refresh
>>>>>>> 7200 ; retry
>>>>>>> 604800 ; expire
>>>>>>> 86400 ) ; default TTL
>>>>>>>
>>>>>>> ;
>>>>>>> ; Zone NS records
>>>>>>> ;
>>>>>>>
>>>>>>> @ NS ns1.goatinatree.com.
>>>>>>> @ NS ns2.goatinatree.com.
>>>>>>>
>>>>>>> ;
>>>>>>> ; Zone records
>>>>>>> ;
>>>>>>>
>>>>>>> @ TXT "v=spf1 a mx ip4:12.45.64.8
>>>>>>> ~all"
>>>>>>> @ A 63.247.73.122
>>>>>>> ftp A 63.247.73.122
>>>>>>> www A 63.247.73.122
>>>>>>> sqlsrv A 216.180.229.66
>>>>>>> websrv A 216.180.229.67
>>>>>>> $TTL 900 ; 15 minutes
>>>>>>> @ MX 5 mail.cvlsoft.net.
>>>>>>> mail A 12.45.64.7
>>>>>>>
>>>>>>> #####################################################
>>>>>>>
>>>>>>>
>>>>>>> I am writing today because I'm trying to see if there is
>>>>>>> anything
>>>>>>> wrong with putting the MX record at the bottom like I did in
>>>>>>> order to
>>>>>>> only have 1 section for 15 minute TTL.
>>>>>>>
>>>>>>> Any help would be much appreciated
>>>>>>>
>>>>>>> Josh
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>
>
>
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